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- Make astpending and need_resched process attributes rather than CPU

Browse source 
attributes.  This is needed for AST's to be properly posted in a preemptive
  kernel.  They are backed by two new flags in p_sflag: PS_ASTPENDING and
  PS_NEEDRESCHED.  They are still accesssed by their old macros:
  aston(), astoff(), etc.  For completeness, an astpending() macro has been
  added to check for a pending AST, and clear_resched() has been added to
  clear need_resched().
- Rename syscall2() on the x86 back to syscall() to be consistent with
  other architectures.
This commit is contained in:
John Baldwin 2001-02-10 02:20:34 +00:00
parent 90b99402a9
commit 142ba5f3d7
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=72276
32 changed files with 171 additions and 227 deletions
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13
sys/alpha/alpha/exception.s
View file

@ -135,14 +135,10 @@ XentSys1: LDGP(pv)
and t1, FRAME_FLAGS_SYSCALL
beq t1, exception_return
ldl t2, GD_ASTPENDING(globalp) /* AST pending? */
beq t2, 2f /* no: return */
/* We've got an AST. Handle it. */
/* Handle any AST's. */
mov sp, a0 /* only arg is frame */
CALL(ast)
2:
/* set the hae register if this process has specified a value */
ldq t0, GD_CURPROC(globalp)
beq t0, 3f
@ -264,12 +260,7 @@ Ler1: LDGP(pv)
and s1, ALPHA_PSL_USERMODE, t0 /* are we returning to user? */
beq t0, Lrestoreregs /* no: just return */
ldl t2, GD_ASTPENDING(globalp) /* AST pending? */
beq t2, Lrestoreregs /* no: return */
/* We've got an AST. Handle it. */
ldiq a0, ALPHA_PSL_IPL_0 /* drop IPL to zero */
call_pal PAL_OSF1_swpipl
/* Handle any AST's or resched's. */
mov sp, a0 /* only arg is frame */
CALL(ast)

1
sys/alpha/alpha/genassym.c
View file

@ -73,7 +73,6 @@ ASSYM(GD_CURPCB, offsetof(struct globaldata, gd_curpcb));
ASSYM(GD_SWITCHTIME, offsetof(struct globaldata, gd_switchtime));
ASSYM(GD_CPUID, offsetof(struct globaldata, gd_cpuid));
ASSYM(GD_IDLEPCBPHYS, offsetof(struct globaldata, gd_idlepcbphys));
ASSYM(GD_ASTPENDING, offsetof(struct globaldata, gd_astpending));
ASSYM(MTX_LOCK, offsetof(struct mtx, mtx_lock));
ASSYM(MTX_RECURSE, offsetof(struct mtx, mtx_recurse));

31
sys/alpha/alpha/trap.c
View file

@ -70,8 +70,6 @@
#include <ddb/ddb.h>
#endif
u_int32_t want_resched;
unsigned long Sfloat_to_reg __P((unsigned int));
unsigned int reg_to_Sfloat __P((unsigned long));
unsigned long Tfloat_reg_cvt __P((unsigned long));
@ -101,7 +99,7 @@ userret(p, frame, oticks)
struct trapframe *frame;
u_quad_t oticks;
{
int sig, s;
int sig;
/* take pending signals */
while ((sig = CURSIG(p)) != 0) {
@ -111,7 +109,7 @@ userret(p, frame, oticks)
}
mtx_lock_spin(&sched_lock);
p->p_priority = p->p_usrpri;
if (want_resched) {
if (resched_wanted()) {
/*
* Since we are curproc, a clock interrupt could
* change our priority without changing run queues
@ -120,14 +118,12 @@ userret(p, frame, oticks)
* before we switch()'ed, we might not be on the queue
* indicated by our priority.
*/
s = splstatclock();
DROP_GIANT_NOSWITCH();
setrunqueue(p);
p->p_stats->p_ru.ru_nivcsw++;
mi_switch();
mtx_unlock_spin(&sched_lock);
PICKUP_GIANT();
splx(s);
while ((sig = CURSIG(p)) != 0) {
if (!mtx_owned(&Giant))
mtx_lock(&Giant);
@ -759,22 +755,27 @@ void
ast(framep)
struct trapframe *framep;
{
register struct proc *p;
struct proc *p = CURPROC;
u_quad_t sticks;
p = curproc;
KASSERT(TRAPF_USERMODE(framep), ("ast in kernel mode"));
/*
* We check for a pending AST here rather than in the assembly as
* acquiring and releasing mutexes in assembly is not fun.
*/
mtx_lock_spin(&sched_lock);
if (!(astpending() || resched_wanted())) {
mtx_unlock_spin(&sched_lock);
return;
}
sticks = p->p_sticks;
mtx_unlock_spin(&sched_lock);
p->p_md.md_tf = framep;
if ((framep->tf_regs[FRAME_PS] & ALPHA_PSL_USERMODE) == 0)
panic("ast and not user");
astoff();
cnt.v_soft++;
PCPU_SET(astpending, 0);
mtx_lock_spin(&sched_lock);
mtx_intr_enable(&sched_lock);
if (p->p_sflag & PS_OWEUPC) {
p->p_sflag &= ~PS_OWEUPC;
mtx_unlock_spin(&sched_lock);

42
sys/alpha/include/cpu.h
View file

@ -62,44 +62,28 @@
struct clockframe {
struct trapframe cf_tf;
};
#define CLKF_USERMODE(framep) \
(((framep)->cf_tf.tf_regs[FRAME_PS] & ALPHA_PSL_USERMODE) != 0)
#define CLKF_PC(framep) ((framep)->cf_tf.tf_regs[FRAME_PC])
#define TRAPF_USERMODE(framep) \
(((framep)->tf_regs[FRAME_PS] & ALPHA_PSL_USERMODE) != 0)
#define TRAPF_PC(framep) ((framep)->tf_regs[FRAME_PC])
#define CLKF_USERMODE(framep) TRAPF_USERMODE(&(framep)->cf_tf)
#define CLKF_PC(framep) TRAPF_PC(&(framep)->cf_tf)
#define CLKF_INTR(framep) (curproc->p_intr_nesting_level >= 2)
/*
* Preempt the current process if in interrupt from user mode,
* or after the current trap/syscall if in system mode.
*/
#define need_resched() do { want_resched = 1; aston(); } while (0)
#define resched_wanted() want_resched
/*
* Give a profiling tick to the current process when the user profiling
* buffer pages are invalid. On the hp300, request an ast to send us
* through trap, marking the proc as needing a profiling tick.
* Arrange to handle pending profiling ticks before returning to user mode.
*
* XXX this is now poorly named and implemented. It used to handle only a
* single tick and the PS_OWEUPC flag served as a counter. Now there is a
* counter in the proc table and flag isn't really necessary.
*/
#define need_proftick(p) do { \
mtx_lock_spin(&sched_lock); \
mtx_lock_spin(&sched_lock); \
(p)->p_sflag |= PS_OWEUPC; \
mtx_unlock_spin(&sched_lock); \
aston(); \
mtx_unlock_spin(&sched_lock); \
} while (0)
/*
* Notify the current process (p) that it has a signal pending,
* process as soon as possible.
*/
#define signotify(p) aston()
#define aston() PCPU_SET(astpending, 1)
#ifdef _KERNEL
extern u_int32_t want_resched; /* resched() was called */
#endif
/*
* CTL_MACHDEP definitions.
*/

1
sys/alpha/include/globaldata.h
View file

@ -57,7 +57,6 @@ struct globaldata {
u_int32_t gd_next_asn; /* next ASN to allocate */
u_int32_t gd_current_asngen; /* ASN rollover check */
u_int gd_astpending;
SLIST_ENTRY(globaldata) gd_allcpu;
int gd_witness_spin_check;
#ifdef KTR_PERCPU

1
sys/alpha/include/pcpu.h
View file

@ -57,7 +57,6 @@ struct globaldata {
u_int32_t gd_next_asn; /* next ASN to allocate */
u_int32_t gd_current_asngen; /* ASN rollover check */
u_int gd_astpending;
SLIST_ENTRY(globaldata) gd_allcpu;
int gd_witness_spin_check;
#ifdef KTR_PERCPU

9
sys/amd64/amd64/apic_vector.S
View file

@ -304,10 +304,9 @@ _Xcpuast:
FAKE_MCOUNT(13*4(%esp))
orl $AST_PENDING, PCPU(ASTPENDING) /* XXX */
MTX_LOCK_SPIN(sched_lock, 0)
movl PCPU(CURPROC),%ebx
incl P_INTR_NESTING_LEVEL(%ebx)
sti
orl $PS_ASTPENDING, P_SFLAG(%ebx)
movl PCPU(CPUID), %eax
lock
@ -315,13 +314,13 @@ _Xcpuast:
lock
btrl %eax, CNAME(resched_cpus)
jnc 2f
orl $AST_PENDING+AST_RESCHED, PCPU(ASTPENDING)
orl $PS_NEEDRESCHED, P_SFLAG(%ebx)
lock
incl CNAME(want_resched_cnt)
2:
MTX_UNLOCK_SPIN(sched_lock)
lock
incl CNAME(cpuast_cnt)
decl P_INTR_NESTING_LEVEL(%ebx)
MEXITCOUNT
jmp _doreti
1:

3
sys/amd64/amd64/cpu_switch.S
View file

@ -180,9 +180,6 @@ sw1a:
sw1b:
movl %eax,%ecx
xorl %eax,%eax
andl $~AST_RESCHED,PCPU(ASTPENDING)
#ifdef INVARIANTS
cmpb $SRUN,P_STAT(%ecx)
jne badsw2

14
sys/amd64/amd64/exception.S
View file

@ -230,7 +230,7 @@ calltrap:
* temporarily altered for the pushfl - an interrupt might come in
* and clobber the saved cs/eip.
*
* We do not obtain the MP lock, but the call to syscall2 might. If it
* We do not obtain the MP lock, but the call to syscall might. If it
* does it will release the lock prior to returning.
*/
SUPERALIGN_TEXT
@ -250,11 +250,8 @@ IDTVEC(syscall)
movl %eax,TF_EFLAGS(%esp)
movl $7,TF_ERR(%esp) /* sizeof "lcall 7,0" */
FAKE_MCOUNT(13*4(%esp))
call _syscall2
call _syscall
MEXITCOUNT
cli /* atomic astpending access */
cmpl $0,PCPU(ASTPENDING) /* AST pending? */
je doreti_syscall_ret /* no, get out of here */
jmp _doreti
/*
@ -264,7 +261,7 @@ IDTVEC(syscall)
* rather then an IGT (interrupt gate). Thus interrupts are enabled on
* entry just as they are for a normal syscall.
*
* We do not obtain the MP lock, but the call to syscall2 might. If it
* We do not obtain the MP lock, but the call to syscall might. If it
* does it will release the lock prior to returning.
*/
SUPERALIGN_TEXT
@ -281,11 +278,8 @@ IDTVEC(int0x80_syscall)
mov %ax,%fs
movl $2,TF_ERR(%esp) /* sizeof "int 0x80" */
FAKE_MCOUNT(13*4(%esp))
call _syscall2
call _syscall
MEXITCOUNT
cli /* atomic astpending access */
cmpl $0,PCPU(ASTPENDING) /* AST pending? */
je doreti_syscall_ret /* no, get out of here */
jmp _doreti
ENTRY(fork_trampoline)

14
sys/amd64/amd64/exception.s
View file

@ -230,7 +230,7 @@ calltrap:
* temporarily altered for the pushfl - an interrupt might come in
* and clobber the saved cs/eip.
*
* We do not obtain the MP lock, but the call to syscall2 might. If it
* We do not obtain the MP lock, but the call to syscall might. If it
* does it will release the lock prior to returning.
*/
SUPERALIGN_TEXT
@ -250,11 +250,8 @@ IDTVEC(syscall)
movl %eax,TF_EFLAGS(%esp)
movl $7,TF_ERR(%esp) /* sizeof "lcall 7,0" */
FAKE_MCOUNT(13*4(%esp))
call _syscall2
call _syscall
MEXITCOUNT
cli /* atomic astpending access */
cmpl $0,PCPU(ASTPENDING) /* AST pending? */
je doreti_syscall_ret /* no, get out of here */
jmp _doreti
/*
@ -264,7 +261,7 @@ IDTVEC(syscall)
* rather then an IGT (interrupt gate). Thus interrupts are enabled on
* entry just as they are for a normal syscall.
*
* We do not obtain the MP lock, but the call to syscall2 might. If it
* We do not obtain the MP lock, but the call to syscall might. If it
* does it will release the lock prior to returning.
*/
SUPERALIGN_TEXT
@ -281,11 +278,8 @@ IDTVEC(int0x80_syscall)
mov %ax,%fs
movl $2,TF_ERR(%esp) /* sizeof "int 0x80" */
FAKE_MCOUNT(13*4(%esp))
call _syscall2
call _syscall
MEXITCOUNT
cli /* atomic astpending access */
cmpl $0,PCPU(ASTPENDING) /* AST pending? */
je doreti_syscall_ret /* no, get out of here */
jmp _doreti
ENTRY(fork_trampoline)

7
sys/amd64/amd64/genassym.c
View file

@ -81,9 +81,13 @@ ASSYM(VM_PMAP, offsetof(struct vmspace, vm_pmap));
ASSYM(PM_ACTIVE, offsetof(struct pmap, pm_active));
ASSYM(P_ADDR, offsetof(struct proc, p_addr));
ASSYM(P_INTR_NESTING_LEVEL, offsetof(struct proc, p_intr_nesting_level));
ASSYM(P_SFLAG, offsetof(struct proc, p_sflag));
ASSYM(P_STAT, offsetof(struct proc, p_stat));
ASSYM(P_WCHAN, offsetof(struct proc, p_wchan));
ASSYM(PS_ASTPENDING, PS_ASTPENDING);
ASSYM(PS_NEEDRESCHED, PS_NEEDRESCHED);
#ifdef SMP
ASSYM(P_ONCPU, offsetof(struct proc, p_oncpu));
ASSYM(P_LASTCPU, offsetof(struct proc, p_lastcpu));
@ -180,9 +184,6 @@ ASSYM(GD_SWITCHTIME, offsetof(struct globaldata, gd_switchtime));
ASSYM(GD_SWITCHTICKS, offsetof(struct globaldata, gd_switchticks));
ASSYM(GD_COMMON_TSSD, offsetof(struct globaldata, gd_common_tssd));
ASSYM(GD_TSS_GDT, offsetof(struct globaldata, gd_tss_gdt));
ASSYM(GD_ASTPENDING, offsetof(struct globaldata, gd_astpending));
ASSYM(AST_PENDING, AST_PENDING);
ASSYM(AST_RESCHED, AST_RESCHED);
#ifdef USER_LDT
ASSYM(GD_CURRENTLDT, offsetof(struct globaldata, gd_currentldt));

3
sys/amd64/amd64/swtch.s
View file

@ -180,9 +180,6 @@ sw1a:
sw1b:
movl %eax,%ecx
xorl %eax,%eax
andl $~AST_RESCHED,PCPU(ASTPENDING)
#ifdef INVARIANTS
cmpb $SRUN,P_STAT(%ecx)
jne badsw2

22
sys/amd64/amd64/trap.c
View file

@ -105,7 +105,7 @@ int (*pmath_emulate) __P((struct trapframe *));
extern void trap __P((struct trapframe frame));
extern int trapwrite __P((unsigned addr));
extern void syscall2 __P((struct trapframe frame));
extern void syscall __P((struct trapframe frame));
extern void ast __P((struct trapframe frame));
static int trap_pfault __P((struct trapframe *, int, vm_offset_t));
@ -212,7 +212,7 @@ userret(p, frame, oticks)
if (!mtx_owned(&Giant))
mtx_lock(&Giant);
mtx_lock_spin(&sched_lock);
addupc_task(p, frame->tf_eip,
addupc_task(p, TRAPF_PC(frame),
(u_int)(p->p_sticks - oticks) * psratio);
}
curpriority = p->p_priority;
@ -1075,7 +1075,7 @@ int trapwrite(addr)
}
/*
* syscall2 - MP aware system call request C handler
* syscall - MP aware system call request C handler
*
* A system call is essentially treated as a trap except that the
* MP lock is not held on entry or return. We are responsible for
@ -1086,7 +1086,7 @@ int trapwrite(addr)
* the current stack is allowed without having to hold MP lock.
*/
void
syscall2(frame)
syscall(frame)
struct trapframe frame;
{
caddr_t params;
@ -1278,10 +1278,22 @@ ast(frame)
struct proc *p = CURPROC;
u_quad_t sticks;
KASSERT(TRAPF_USERMODE(&frame), ("ast in kernel mode"));
/*
* We check for a pending AST here rather than in the assembly as
* acquiring and releasing mutexes in assembly is not fun.
*/
mtx_lock_spin(&sched_lock);
if (!(astpending() || resched_wanted())) {
mtx_unlock_spin(&sched_lock);
return;
}
sticks = p->p_sticks;
astoff();
mtx_intr_enable(&sched_lock);
atomic_add_int(&cnt.v_soft, 1);
if (p->p_sflag & PS_OWEUPC) {
p->p_sflag &= ~PS_OWEUPC;

44
sys/amd64/include/cpu.h
View file

@ -59,31 +59,16 @@
#define cpu_getstack(p) ((p)->p_md.md_regs->tf_esp)
#define cpu_setstack(p, ap) ((p)->p_md.md_regs->tf_esp = (ap))
#define TRAPF_USERMODE(framep) \
((ISPL((framep)->tf_cs) == SEL_UPL) || ((framep)->tf_eflags & PSL_VM))
#define TRAPF_PC(framep) ((framep)->tf_eip)
#define CLKF_USERMODE(framep) \
((ISPL((framep)->cf_cs) == SEL_UPL) || (framep->cf_eflags & PSL_VM))
((ISPL((framep)->cf_cs) == SEL_UPL) || ((framep)->cf_eflags & PSL_VM))
#define CLKF_INTR(framep) (curproc->p_intr_nesting_level >= 2)
#define CLKF_PC(framep) ((framep)->cf_eip)
/*
* astpending bits
*/
#define AST_PENDING 0x00000001
#define AST_RESCHED 0x00000002
/*
* Preempt the current process if in interrupt from user mode,
* or after the current trap/syscall if in system mode.
*
* XXX: if astpending is later changed to an |= here due to more flags being
* added, we will have an atomicy problem. The type of atomicy we need is
* a non-locked orl.
*/
#define need_resched() do { \
PCPU_SET(astpending, AST_RESCHED|AST_PENDING); \
} while (0)
#define resched_wanted() (PCPU_GET(astpending) & AST_RESCHED)
/*
* Arrange to handle pending profiling ticks before returning to user mode.
*
@ -92,27 +77,12 @@
* counter in the proc table and flag isn't really necessary.
*/
#define need_proftick(p) do { \
mtx_lock_spin(&sched_lock); \
mtx_lock_spin(&sched_lock); \
(p)->p_sflag |= PS_OWEUPC; \
mtx_unlock_spin(&sched_lock); \
aston(); \
mtx_unlock_spin(&sched_lock); \
} while (0)
/*
* Notify the current process (p) that it has a signal pending,
* process as soon as possible.
*
* XXX: aston() really needs to be an atomic (not locked, but an orl),
* in case need_resched() is set by an interrupt. But with astpending a
* per-cpu variable this is not trivial to do efficiently. For now we blow
* it off (asynchronous need_resched() conflicts are not critical).
*/
#define signotify(p) aston()
#define aston() do { \
PCPU_SET(astpending, PCPU_GET(astpending) | AST_PENDING); \
} while (0)
#define astoff()
/*
* CTL_MACHDEP definitions.
*/

1
sys/amd64/include/pcpu.h
View file

@ -63,7 +63,6 @@ struct globaldata {
int gd_currentldt; /* only used for USER_LDT */
u_int gd_cpuid;
u_int gd_other_cpus;
u_int gd_astpending;
SLIST_ENTRY(globaldata) gd_allcpu;
int gd_witness_spin_check;
#ifdef KTR_PERCPU

9
sys/i386/i386/apic_vector.s
View file

@ -304,10 +304,9 @@ _Xcpuast:
FAKE_MCOUNT(13*4(%esp))
orl $AST_PENDING, PCPU(ASTPENDING) /* XXX */
MTX_LOCK_SPIN(sched_lock, 0)
movl PCPU(CURPROC),%ebx
incl P_INTR_NESTING_LEVEL(%ebx)
sti
orl $PS_ASTPENDING, P_SFLAG(%ebx)
movl PCPU(CPUID), %eax
lock
@ -315,13 +314,13 @@ _Xcpuast:
lock
btrl %eax, CNAME(resched_cpus)
jnc 2f
orl $AST_PENDING+AST_RESCHED, PCPU(ASTPENDING)
orl $PS_NEEDRESCHED, P_SFLAG(%ebx)
lock
incl CNAME(want_resched_cnt)
2:
MTX_UNLOCK_SPIN(sched_lock)
lock
incl CNAME(cpuast_cnt)
decl P_INTR_NESTING_LEVEL(%ebx)
MEXITCOUNT
jmp _doreti
1:

14
sys/i386/i386/exception.s
View file

@ -230,7 +230,7 @@ calltrap:
* temporarily altered for the pushfl - an interrupt might come in
* and clobber the saved cs/eip.
*
* We do not obtain the MP lock, but the call to syscall2 might. If it
* We do not obtain the MP lock, but the call to syscall might. If it
* does it will release the lock prior to returning.
*/
SUPERALIGN_TEXT
@ -250,11 +250,8 @@ IDTVEC(syscall)
movl %eax,TF_EFLAGS(%esp)
movl $7,TF_ERR(%esp) /* sizeof "lcall 7,0" */
FAKE_MCOUNT(13*4(%esp))
call _syscall2
call _syscall
MEXITCOUNT
cli /* atomic astpending access */
cmpl $0,PCPU(ASTPENDING) /* AST pending? */
je doreti_syscall_ret /* no, get out of here */
jmp _doreti
/*
@ -264,7 +261,7 @@ IDTVEC(syscall)
* rather then an IGT (interrupt gate). Thus interrupts are enabled on
* entry just as they are for a normal syscall.
*
* We do not obtain the MP lock, but the call to syscall2 might. If it
* We do not obtain the MP lock, but the call to syscall might. If it
* does it will release the lock prior to returning.
*/
SUPERALIGN_TEXT
@ -281,11 +278,8 @@ IDTVEC(int0x80_syscall)
mov %ax,%fs
movl $2,TF_ERR(%esp) /* sizeof "int 0x80" */
FAKE_MCOUNT(13*4(%esp))
call _syscall2
call _syscall
MEXITCOUNT
cli /* atomic astpending access */
cmpl $0,PCPU(ASTPENDING) /* AST pending? */
je doreti_syscall_ret /* no, get out of here */
jmp _doreti
ENTRY(fork_trampoline)

7
sys/i386/i386/genassym.c
View file

@ -81,9 +81,13 @@ ASSYM(VM_PMAP, offsetof(struct vmspace, vm_pmap));
ASSYM(PM_ACTIVE, offsetof(struct pmap, pm_active));
ASSYM(P_ADDR, offsetof(struct proc, p_addr));
ASSYM(P_INTR_NESTING_LEVEL, offsetof(struct proc, p_intr_nesting_level));
ASSYM(P_SFLAG, offsetof(struct proc, p_sflag));
ASSYM(P_STAT, offsetof(struct proc, p_stat));
ASSYM(P_WCHAN, offsetof(struct proc, p_wchan));
ASSYM(PS_ASTPENDING, PS_ASTPENDING);
ASSYM(PS_NEEDRESCHED, PS_NEEDRESCHED);
#ifdef SMP
ASSYM(P_ONCPU, offsetof(struct proc, p_oncpu));
ASSYM(P_LASTCPU, offsetof(struct proc, p_lastcpu));
@ -180,9 +184,6 @@ ASSYM(GD_SWITCHTIME, offsetof(struct globaldata, gd_switchtime));
ASSYM(GD_SWITCHTICKS, offsetof(struct globaldata, gd_switchticks));
ASSYM(GD_COMMON_TSSD, offsetof(struct globaldata, gd_common_tssd));
ASSYM(GD_TSS_GDT, offsetof(struct globaldata, gd_tss_gdt));
ASSYM(GD_ASTPENDING, offsetof(struct globaldata, gd_astpending));
ASSYM(AST_PENDING, AST_PENDING);
ASSYM(AST_RESCHED, AST_RESCHED);
#ifdef USER_LDT
ASSYM(GD_CURRENTLDT, offsetof(struct globaldata, gd_currentldt));

3
sys/i386/i386/swtch.s
View file

@ -180,9 +180,6 @@ sw1a:
sw1b:
movl %eax,%ecx
xorl %eax,%eax
andl $~AST_RESCHED,PCPU(ASTPENDING)
#ifdef INVARIANTS
cmpb $SRUN,P_STAT(%ecx)
jne badsw2

22
sys/i386/i386/trap.c
View file

@ -105,7 +105,7 @@ int (*pmath_emulate) __P((struct trapframe *));
extern void trap __P((struct trapframe frame));
extern int trapwrite __P((unsigned addr));
extern void syscall2 __P((struct trapframe frame));
extern void syscall __P((struct trapframe frame));
extern void ast __P((struct trapframe frame));
static int trap_pfault __P((struct trapframe *, int, vm_offset_t));
@ -212,7 +212,7 @@ userret(p, frame, oticks)
if (!mtx_owned(&Giant))
mtx_lock(&Giant);
mtx_lock_spin(&sched_lock);
addupc_task(p, frame->tf_eip,
addupc_task(p, TRAPF_PC(frame),
(u_int)(p->p_sticks - oticks) * psratio);
}
curpriority = p->p_priority;
@ -1075,7 +1075,7 @@ int trapwrite(addr)
}
/*
* syscall2 - MP aware system call request C handler
* syscall - MP aware system call request C handler
*
* A system call is essentially treated as a trap except that the
* MP lock is not held on entry or return. We are responsible for
@ -1086,7 +1086,7 @@ int trapwrite(addr)
* the current stack is allowed without having to hold MP lock.
*/
void
syscall2(frame)
syscall(frame)
struct trapframe frame;
{
caddr_t params;
@ -1278,10 +1278,22 @@ ast(frame)
struct proc *p = CURPROC;
u_quad_t sticks;
KASSERT(TRAPF_USERMODE(&frame), ("ast in kernel mode"));
/*
* We check for a pending AST here rather than in the assembly as
* acquiring and releasing mutexes in assembly is not fun.
*/
mtx_lock_spin(&sched_lock);
if (!(astpending() || resched_wanted())) {
mtx_unlock_spin(&sched_lock);
return;
}
sticks = p->p_sticks;
astoff();
mtx_intr_enable(&sched_lock);
atomic_add_int(&cnt.v_soft, 1);
if (p->p_sflag & PS_OWEUPC) {
p->p_sflag &= ~PS_OWEUPC;

2
sys/i386/include/asnames.h
View file

@ -304,7 +304,7 @@
#define _swi_net swi_net
#define _swi_null swi_null
#define _swi_vm swi_vm
#define _syscall2 syscall2
#define _syscall syscall
#define _szsigcode szsigcode
#define _ticks ticks
#define _time time

44
sys/i386/include/cpu.h
View file

@ -59,31 +59,16 @@
#define cpu_getstack(p) ((p)->p_md.md_regs->tf_esp)
#define cpu_setstack(p, ap) ((p)->p_md.md_regs->tf_esp = (ap))
#define TRAPF_USERMODE(framep) \
((ISPL((framep)->tf_cs) == SEL_UPL) || ((framep)->tf_eflags & PSL_VM))
#define TRAPF_PC(framep) ((framep)->tf_eip)
#define CLKF_USERMODE(framep) \
((ISPL((framep)->cf_cs) == SEL_UPL) || (framep->cf_eflags & PSL_VM))
((ISPL((framep)->cf_cs) == SEL_UPL) || ((framep)->cf_eflags & PSL_VM))
#define CLKF_INTR(framep) (curproc->p_intr_nesting_level >= 2)
#define CLKF_PC(framep) ((framep)->cf_eip)
/*
* astpending bits
*/
#define AST_PENDING 0x00000001
#define AST_RESCHED 0x00000002
/*
* Preempt the current process if in interrupt from user mode,
* or after the current trap/syscall if in system mode.
*
* XXX: if astpending is later changed to an |= here due to more flags being
* added, we will have an atomicy problem. The type of atomicy we need is
* a non-locked orl.
*/
#define need_resched() do { \
PCPU_SET(astpending, AST_RESCHED|AST_PENDING); \
} while (0)
#define resched_wanted() (PCPU_GET(astpending) & AST_RESCHED)
/*
* Arrange to handle pending profiling ticks before returning to user mode.
*
@ -92,27 +77,12 @@
* counter in the proc table and flag isn't really necessary.
*/
#define need_proftick(p) do { \
mtx_lock_spin(&sched_lock); \
mtx_lock_spin(&sched_lock); \
(p)->p_sflag |= PS_OWEUPC; \
mtx_unlock_spin(&sched_lock); \
aston(); \
mtx_unlock_spin(&sched_lock); \
} while (0)
/*
* Notify the current process (p) that it has a signal pending,
* process as soon as possible.
*
* XXX: aston() really needs to be an atomic (not locked, but an orl),
* in case need_resched() is set by an interrupt. But with astpending a
* per-cpu variable this is not trivial to do efficiently. For now we blow
* it off (asynchronous need_resched() conflicts are not critical).
*/
#define signotify(p) aston()
#define aston() do { \
PCPU_SET(astpending, PCPU_GET(astpending) | AST_PENDING); \
} while (0)
#define astoff()
/*
* CTL_MACHDEP definitions.
*/

1
sys/i386/include/globaldata.h
View file

@ -63,7 +63,6 @@ struct globaldata {
int gd_currentldt; /* only used for USER_LDT */
u_int gd_cpuid;
u_int gd_other_cpus;
u_int gd_astpending;
SLIST_ENTRY(globaldata) gd_allcpu;
int gd_witness_spin_check;
#ifdef KTR_PERCPU

1
sys/i386/include/pcpu.h
View file

@ -63,7 +63,6 @@ struct globaldata {
int gd_currentldt; /* only used for USER_LDT */
u_int gd_cpuid;
u_int gd_other_cpus;
u_int gd_astpending;
SLIST_ENTRY(globaldata) gd_allcpu;
int gd_witness_spin_check;
#ifdef KTR_PERCPU

9
sys/i386/isa/apic_vector.s
View file

@ -304,10 +304,9 @@ _Xcpuast:
FAKE_MCOUNT(13*4(%esp))
orl $AST_PENDING, PCPU(ASTPENDING) /* XXX */
MTX_LOCK_SPIN(sched_lock, 0)
movl PCPU(CURPROC),%ebx
incl P_INTR_NESTING_LEVEL(%ebx)
sti
orl $PS_ASTPENDING, P_SFLAG(%ebx)
movl PCPU(CPUID), %eax
lock
@ -315,13 +314,13 @@ _Xcpuast:
lock
btrl %eax, CNAME(resched_cpus)
jnc 2f
orl $AST_PENDING+AST_RESCHED, PCPU(ASTPENDING)
orl $PS_NEEDRESCHED, P_SFLAG(%ebx)
lock
incl CNAME(want_resched_cnt)
2:
MTX_UNLOCK_SPIN(sched_lock)
lock
incl CNAME(cpuast_cnt)
decl P_INTR_NESTING_LEVEL(%ebx)
MEXITCOUNT
jmp _doreti
1:

18
sys/i386/isa/ipl.s
View file

@ -55,17 +55,20 @@
SUPERALIGN_TEXT
.type _doreti,@function
_doreti:
FAKE_MCOUNT(_bintr) /* init "from" _bintr -> _doreti */
doreti_next:
/* Check for ASTs that can be handled now. */
testl $AST_PENDING,PCPU(ASTPENDING)
je doreti_exit /* no AST, exit */
testb $SEL_RPL_MASK,TF_CS(%esp) /* are we in user mode? */
jne doreti_ast /* yes, do it now. */
testl $PSL_VM,TF_EFLAGS(%esp) /* kernel mode */
je doreti_exit /* and not VM86 mode, defer */
cmpl $1,_in_vm86call /* are we in a VM86 call? */
jne doreti_ast /* yes, we can do it */
je doreti_exit /* no, defer */
doreti_ast:
movl $T_ASTFLT,TF_TRAPNO(%esp)
call _ast
/*
* doreti_exit: release MP lock, pop registers, iret.
@ -80,7 +83,6 @@ doreti_exit:
.globl doreti_popl_fs
.globl doreti_syscall_ret
doreti_syscall_ret:
doreti_popl_fs:
popl %fs
.globl doreti_popl_es
@ -120,14 +122,6 @@ doreti_popl_fs_fault:
movl $T_PROTFLT,TF_TRAPNO(%esp)
jmp alltraps_with_regs_pushed
ALIGN_TEXT
doreti_ast:
andl $~AST_PENDING,PCPU(ASTPENDING)
sti
movl $T_ASTFLT,TF_TRAPNO(%esp)
call _ast
jmp doreti_next
#ifdef APIC_IO
#include "i386/isa/apic_ipl.s"
#else

2
sys/kern/kern_sig.c
View file

@ -1251,8 +1251,8 @@ psignal(p, sig)
* It will either never be noticed, or noticed very soon.
*/
if (p == curproc) {
mtx_unlock_spin(&sched_lock);
signotify(p);
mtx_unlock_spin(&sched_lock);
}
#ifdef SMP
else if (p->p_stat == SRUN) {

22
sys/kern/subr_trap.c
View file

@ -105,7 +105,7 @@ int (*pmath_emulate) __P((struct trapframe *));
extern void trap __P((struct trapframe frame));
extern int trapwrite __P((unsigned addr));
extern void syscall2 __P((struct trapframe frame));
extern void syscall __P((struct trapframe frame));
extern void ast __P((struct trapframe frame));
static int trap_pfault __P((struct trapframe *, int, vm_offset_t));
@ -212,7 +212,7 @@ userret(p, frame, oticks)
if (!mtx_owned(&Giant))
mtx_lock(&Giant);
mtx_lock_spin(&sched_lock);
addupc_task(p, frame->tf_eip,
addupc_task(p, TRAPF_PC(frame),
(u_int)(p->p_sticks - oticks) * psratio);
}
curpriority = p->p_priority;
@ -1075,7 +1075,7 @@ int trapwrite(addr)
}
/*
* syscall2 - MP aware system call request C handler
* syscall - MP aware system call request C handler
*
* A system call is essentially treated as a trap except that the
* MP lock is not held on entry or return. We are responsible for
@ -1086,7 +1086,7 @@ int trapwrite(addr)
* the current stack is allowed without having to hold MP lock.
*/
void
syscall2(frame)
syscall(frame)
struct trapframe frame;
{
caddr_t params;
@ -1278,10 +1278,22 @@ ast(frame)
struct proc *p = CURPROC;
u_quad_t sticks;
KASSERT(TRAPF_USERMODE(&frame), ("ast in kernel mode"));
/*
* We check for a pending AST here rather than in the assembly as
* acquiring and releasing mutexes in assembly is not fun.
*/
mtx_lock_spin(&sched_lock);
if (!(astpending() || resched_wanted())) {
mtx_unlock_spin(&sched_lock);
return;
}
sticks = p->p_sticks;
astoff();
mtx_intr_enable(&sched_lock);
atomic_add_int(&cnt.v_soft, 1);
if (p->p_sflag & PS_OWEUPC) {
p->p_sflag &= ~PS_OWEUPC;

1
sys/powerpc/include/globaldata.h
View file

@ -57,7 +57,6 @@ struct globaldata {
u_int32_t gd_next_asn; /* next ASN to allocate */
u_int32_t gd_current_asngen; /* ASN rollover check */
u_int gd_astpending;
SLIST_ENTRY(globaldata) gd_allcpu;
int gd_witness_spin_check;
#ifdef KTR_PERCPU

1
sys/powerpc/include/pcpu.h
View file

@ -57,7 +57,6 @@ struct globaldata {
u_int32_t gd_next_asn; /* next ASN to allocate */
u_int32_t gd_current_asngen; /* ASN rollover check */
u_int gd_astpending;
SLIST_ENTRY(globaldata) gd_allcpu;
int gd_witness_spin_check;
#ifdef KTR_PERCPU

1
sys/powerpc/powerpc/genassym.c
View file

@ -73,7 +73,6 @@ ASSYM(GD_CURPCB, offsetof(struct globaldata, gd_curpcb));
ASSYM(GD_SWITCHTIME, offsetof(struct globaldata, gd_switchtime));
ASSYM(GD_CPUID, offsetof(struct globaldata, gd_cpuid));
ASSYM(GD_IDLEPCBPHYS, offsetof(struct globaldata, gd_idlepcbphys));
ASSYM(GD_ASTPENDING, offsetof(struct globaldata, gd_astpending));
ASSYM(MTX_LOCK, offsetof(struct mtx, mtx_lock));
ASSYM(MTX_RECURSE, offsetof(struct mtx, mtx_recurse));

35
sys/sys/proc.h
View file

@ -329,6 +329,8 @@ struct proc {
#define PS_CVWAITQ 0x00080 /* Proces is on a cv_waitq (not slpq). */
#define PS_SWAPINREQ 0x00100 /* Swapin request due to wakeup. */
#define PS_SWAPPING 0x00200 /* Process is being swapped. */
#define PS_ASTPENDING 0x00400 /* Process has a pending ast. */
#define PS_NEEDRESCHED 0x00800 /* Process needs to yield. */
#define P_MAGIC 0xbeefface
@ -378,6 +380,39 @@ sigonstack(size_t sp)
: 0);
}
/*
* Preempt the current process if in interrupt from user mode,
* or after the current trap/syscall if in system mode.
*/
#define need_resched() do { \
mtx_assert(&sched_lock, MA_OWNED); \
curproc->p_sflag |= PS_NEEDRESCHED; \
} while (0)
#define resched_wanted() (curproc->p_sflag & PS_NEEDRESCHED)
#define clear_resched() do { \
mtx_assert(&sched_lock, MA_OWNED); \
curproc->p_sflag &= ~PS_NEEDRESCHED; \
} while (0)
/*
* Notify the current process (p) that it has a signal pending,
* process as soon as possible.
*/
#define aston() signotify(CURPROC)
#define signotify(p) do { \
mtx_assert(&sched_lock, MA_OWNED); \
(p)->p_sflag |= PS_ASTPENDING; \
} while (0)
#define astpending() (curproc->p_sflag & PS_ASTPENDING)
#define astoff() do { \
mtx_assert(&sched_lock, MA_OWNED); \
CURPROC->p_sflag &= ~PS_ASTPENDING; \
} while (0)
/* Handy macro to determine if p1 can mangle p2. */
#define PRISON_CHECK(p1, p2) \
((p1)->p_prison == NULL || (p1)->p_prison == (p2)->p_prison)